PHYS 102 Chapter Notes - Chapter 25: Shutter Speed, Virtual Image, Retina
35
PHYS 102 Full Course Notes
Verified Note
35 documents
Document Summary
A camera lens forms an image on film, or on a charge-coupled device in a digital camera, by allowing light in through a shutter. adjusted for the brightness of the scene and the chosen shutter speed. The lens is focused by moving it relative to the film, and its -stop (or lens opening) must be. The -stop is defined as the ratio of the focal length to the diameter of the lens opening. The human eye also adjusts for the available light: by opening and closing the iris. It focuses not by moving the lens, but by adjusting the shape of the lens to vary its focal length. The image is formed on the retina, which contains an array of receptors known as rods and cones. Diverging eye-glass or contact lenses are used to correct the defect of a nearsighted eye, which cannot focus well on distant objects.
